Petroleum fractions used for jet fuel are typically qualified in part by an ASTM standard (ASTM D3241) to verify the suitability (ASTM D1655) of a petroleum fraction for use. Once a fraction is found to meet the specification from ASTM D1655, it is conventionally assumed that a jet fuel fraction and/or a finished blended jet fuel product will remain stable over time and therefore will remain within the specification limits and not need subsequent testing for requalification for use.
One of the difficulties in applying ASTM D3241 and/or D1655 is that these measurements provide a snapshot of the characteristics of a jet fuel fraction and/or finished jet fuel product. By contrast, the specification for stability of a jet fuel fraction corresponds to a stability over the course of time, such as a period of months or possibly a year or greater. Naturally, waiting an extended period of time to perform a characterization test for a jet fuel fraction and/or finished jet fuel product can lead to variety of logistical difficulties in identifying suitable crude fractions for forming jet fuels. In order to overcome some of these difficulties, a characterization method based on accelerated aging was developed and described in pending U.S. application Ser. No. 14/021,028. However, the method described in Ser. No. 14/021,028 still corresponds to a time-consuming method for determining whether a potential jet fuel product is fit for purpose.
Use of quartz crystals as part of a measurement apparatus, such as in a Quartz Crystal Microbalance (QCM) apparatus, has previously been described in various literature references. Although a variety of configurations may be suitable for construction of an apparatus incorporating a quartz crystal, one standard option for constructing a QCM apparatus is described in ASTM D7739.